Accessory apparatus and camera system

A camera system comprising:

• an accessory apparatus;
• and
• an image capturing apparatus to which the accessory apparatus is attachable and which includes a power source configured to supply power to the accessory apparatus through a first electrical contact and an electrical contact capable of connecting a second electrical contact to a reference potential in a state where the accessory apparatus is attached to the image capturing apparatus,
• wherein the accessory apparatus is attachable to and detachable from the image capturing apparatus and is moved in a predetermined direction with respect to the image capturing apparatus so that the accessory apparatus is detached from the image capturing apparatus, and
• wherein the accessory apparatus includes:
• the first electrical contact configured to receive power from the image capturing apparatus in a state of being attached to the image capturing apparatus;
• the second electrical contact disposed on a predetermined direction side of the first electrical contact, configured to be connected to a predetermined electrical contact connected to the reference potential of the image capturing apparatus in the state of being attached to the image capturing apparatus, and configured to be unconnected from the reference potential during removal from the image capturing apparatus;
• a capacitor device with one end connected to the first electrical contact and another end connected to the second electrical contact;
• and
• a reduction unit configured to reduce charge stored in the capacitor device during the removal from the image capturing apparatus.